U.S. patent number 4,893,669 [Application Number 07/286,291] was granted by the patent office on 1990-01-16 for synthetic resin heat exchanger unit used for cooling tower and cooling tower utilizing heat exchanger consisting of such heat exchanger unit.
This patent grant is currently assigned to Shinwa Sangyo Co., Ltd.. Invention is credited to Ken Kashiwada, Tadanobu Muto, Tetsuo Sasaki.
United States Patent |
4,893,669 |
Kashiwada , et al. |
January 16, 1990 |
Synthetic resin heat exchanger unit used for cooling tower and
cooling tower utilizing heat exchanger consisting of such heat
exchanger unit
Abstract
The invention provides flat, thin and hollow heat exchanger
units of synthetic resin make, each operating to have a cooling
water fed thereto and air flowed horizontally in an air passage
therebetween, thus realizing an indirect contact heat exchange
between the air and the cooling water through both wall plates. The
invention further relates to a crossflow cooling tower
incorporating a wet heat exchanger or packing material and an
indirect contact type heat exchanger operating on the
afore-mentioned heat exchanger units.
Inventors: |
Kashiwada; Ken (Fujisawa,
JP), Muto; Tadanobu (Tokyo, JP), Sasaki;
Tetsuo (Fujisawa, JP) |
Assignee: |
Shinwa Sangyo Co., Ltd. (Tokyo,
JP)
|
Family
ID: |
26362981 |
Appl.
No.: |
07/286,291 |
Filed: |
December 19, 1988 |
Foreign Application Priority Data
|
|
|
|
|
Feb 5, 1988 [JP] |
|
|
62-25388 |
Mar 17, 1988 [JP] |
|
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62-64536 |
|
Current U.S.
Class: |
165/282; 165/103;
165/166; 165/900; 261/DIG.77; 165/46; 165/115; 165/170; 165/905;
261/153 |
Current CPC
Class: |
F28F
21/065 (20130101); F28C 1/04 (20130101); F28D
1/0316 (20130101); F28C 1/14 (20130101); Y10S
165/905 (20130101); Y10S 261/77 (20130101); Y10S
165/90 (20130101); Y02B 30/70 (20130101) |
Current International
Class: |
F28C
1/00 (20060101); F28F 21/00 (20060101); F28D
1/02 (20060101); F28C 1/04 (20060101); F28C
1/14 (20060101); F28F 21/06 (20060101); F28D
1/03 (20060101); G05D 015/00 (); F28F 003/00 ();
F28F 021/06 () |
Field of
Search: |
;165/32,38,46,103,115,166,170,900,905 ;261/153 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Ford; John
Attorney, Agent or Firm: Oblon, Spivak, McClelland, Maier
& Neustadt
Claims
What is claimed is:
1. A synthetic resin heat exchanger unit used for a cooling tower,
of a flat and thin hollow body formed as a whole by two wall plates
wherein the interior functions as a liquid flowing passage, a
cooling water feed part open externally is formed on an upper
portion of the hollow body, a discharge part open externally is
also provided on a lower end of the liquid flowing passage which is
a lower edge of the hollow body, a major breadth portion of the
liquid flowing passage forms a liquid falling speed reducing part,
the liquid falling speed reducing part has horizontally extending
deflectors distributed vertically throughout the unit each defining
a stage, the deflectors are dislocated every other to form a zigzag
passage therebetween;
said heat exchanger unit being characterized in that the liquid
falling speed reducing part is disposed to abut on a vertically
extending overflowed-liquid escaping conduit through one vertical
sealing part at least, an upper end of the vertical sealing part is
shaped like a dam, said overflowed-liquid escaping conduit and a
reservoir portion on the uppermost stage in the liquid falling
speed reducing part communicate with each other through the dam,
and an air vent crosses over said vertical sealing part and opens
into said overflowed-liquid escaping conduit and is formed at a
bent position of said zigzag liquid falling speed reducing part,
and a raise is formed as a spacer on outer surfaces of both said
wall plates.
2. The synthetic resin heat exchanger unit used for a cooling tower
according to claim 1, wherein said hollow body is a vacuum or blow
molding.
3. The synthetic resin heat exchanger unit used for a cooling tower
according to claim 1, wherein said overflowed-liquid escaping
conduit is provided along one side edge of said hollow body.
4. The synthetic resin heat exchanger unit used for a cooling tower
according to claim 1, wherein said overflowed-liquid escaping
conduit is provided along both side edges of said hollow body.
5. The synthetic resin heat exchanger unit used for a cooling tower
according to claim 1, wherein said liquid falling speed reducing
part is separated into at least two sequences of liquid flowing
passages at the central portion by a vertical partition sealing
portion.
6. The synthetic resin heat exchanger unit used for a cooling tower
according to claim 1, wherein parallel ridges inclined gradually up
to approximately 45 degrees toward a downstream direction are
formed on surfaces inside of both wall plates constituting said
liquid falling speed reducing part.
7. The synthetic resin heat exchanger unit used for a cooling tower
according to claim 1, wherein a cylindrical discharge port is
provided on a lower edge corner of said hollow body as said
discharge port.
8. The synthetic resin heat exchanger unit used for a cooling tower
according to claim 1, wherein said discharge port is formed by
opening a lower edge of said hollow body in full width.
9. The synthetic resin heat exchanger unit used for a cooling tower
according to claim 1, wherein an upper edge of said hollow body is
opened in full width and both wall plates of the upper edge are
overhung outwardly at the height even with said raise, a central
portion of the upper edge is formed in a U-shaped recession, and
said feed part is formed of a bottom portion of the recession.
10. In a crossflow cooling tower incorporating within a frame an
indirect contact type heat exchanger which comprises a plurality of
synthetic resin heat exchanger units of a flat and thin hollow body
formed as a whole by two wall plates which are arranged in parallel
with each other wherein the interior functions as a liquid flowing
passage, a cooling water feed part open externally is formed on an
upper portion of the hollow body, a discharge part open externally
is also provided on a lower end of the liquid flowing passage which
is a lower edge of the hollow body, a major breadth portion of the
liquid flowing passage forms a liquid falling speed reducing part,
the liquid falling speed reducing part has horizontally extending
deflectors distributed vertically throughout the unit each defining
a stage, a zigzag passage being formed between the deflectors, and
using a raise formed on front and pack of these heat exchanger
units as a spacer, forming a horizontal air flowing passage between
the adjacent heat exchanger units;
the improvement characterized in that the liquid speed reducing
part is disposed to abut on a vertically extending
overflowed-liquid escaping conduit through one vertical sealing
part at least, an upper end of the vertical sealing part is shaped
like a dam, said overflowed-liquid escaping conduit and reservoir
portion on the uppermost stage in the liquid falling speed reducing
part communicate with each other through the dam and an air vent
crosses over said vertical sealing part and opens into said
overflowed-liquid escaping conduit and is formed at a bent portion
of said zigzag liquid falling speed reducing part, an upper edge of
the hollow body is opened in full width and both wall plates of the
upper edge are overhung outwardly, a central portion of the upper
edge is formed into a U-shaped recession, said cooling water feed
part is formed of a bottom of the recession, said cooling water
feed parts come in contact close with each other to form a
temporary cooling water storage part along an upper edge of said
indirect contact type heat exchanger at the time when said heat
exchanger units are arrayed adjacently in sequence.
11. The crossflow cooling tower according to claim 10, wherein fist
said indirect contact type heat exchangers are disposed in parallel
on the inside of a wet heat exchanger disposed on a lower side of
an upper water tank of said cooling tower, further a second said
indirect contact type heat exchanger is disposed vertically between
the wet heat exchanger and the upper water tank, the combined
height of first said indirect contact type heat exchangers equaling
the heights of said wet heat exchanger and second indirect contact
type heat exchanger together, a feed part for said first and second
indirect contact type heat exchangers is open to face a sprinkling
hole in a bottom of the upper water tank.
12. The crossflow cooling tower according to claim 10, wherein
first said indirect contact type heat exchangers are disposed in
parallel on the inside and outside of a wet heat exchanger disposed
on a lower side of an upper water tank of said cooling tower,
further a second said indirect contact type heat exchanger is
disposed vertically between the wet exchanger and the upper water
tank, the combined height of first said indirect contract type heat
exchangers equaling the heights of said wet heat exchanger and
second said indirect contact type heat exchanger together, a nose
of a distributing pipe extending from the upper water tank is open
to a feed part of the inside indirect contact type heat exchanger,
a feed part of the outside indirect contact type heat exchanger is
open to face a sprinkling hole in a bottom of the upper water
tank.
13. The crossflow cooling tower according to claim 10, wherein said
indirect contact type heat exchanger is provided above a wet heat
exchanger with a first sprinkler interposed therebetween, a second
sprinkler for applying water to an air contact surface of said
indirect contact type heat exchanger is provided on an upper
portion of said indirect contact type heat exchanger, a second
supply pipe branched from said supply pipe through a transfer valve
is connected to said second sprinkler.
14. The crossflow cooling tower according to claim 10, wherein each
heat exchanger unit having a liquid flowing passage formed therein
has at least a draft part opened to the air at each upper supplying
part, each lower discharge part is connected to a common
air-communicating lower cooling water storage tank.
15. The cross flow cooling tower according to claim 10, which
comprises an air intake port facing on an air blow-off port of the
air passage of said indirect contact type heat exchanger, having
disposed therein a plurality of dry/wet air mixing cylinders
projectingly and being horizontally downward of an exhaust port, an
air intake height of the cylinders coinciding with an overall
height of the air blow-off port, wherein:
a nose portion of each cylinder is closed, an air discharge port is
opened on a peripheral surface of the cylinder from an air blow-off
port side toward a nose side, said cylinders each function as a dry
air release guide chamber internally.
16. The crossflow cooling tower according to claim 15, wherein the
air discharge port of said cylinder is perforated in an upper wall
of the cylinder.
17. The crossflow cooling tower according to claim 15, wherein a
wet air intake port open into the cylinder is perforated in a
bottom portion of said cylinder.
18. The crossflow cooling tower according to claim 15, wherein said
cylinder is made of synthetic resin.
19. The crossflow cooling tower according to claim 15, wherein the
air discharge port of said cylinder is perforated in opposite side
walls of the cylinder.
20. The crossflow cooling tower according to claim 15, wherein an
upper wall of the cylinder in which the air discharge port for said
cylinder is perforated is inclined to extend downward from an upper
end of the air blow-off port of the dry heat exchanger downward of
said blower so as to keep away from blades of the blower, a bottom
of the cylinder is inclined upward, counter to the upper wall, from
a lower end of the air blow-off port downward of said blower, thus
functioning as a drop receiving part.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a heat exchanger unit used for a cooling
tower and a cooling tower utilizing a heat exchanger consisting of
such heat exchanger unit.
2. Discussion of Background
Such kind of indirect contact type heat exchanger has already been
disclosed in Japanese Unexamined Patent Publication No.
100370/1976, referring to a heat exchanger used for a cooling tower
which is constructed entirely of synthetic resin and provided with
a plurality of liquid flowing passages flat, vertical and parallel
with each other, and air flowing passages flat to have a vertical
plane each which are formed between the liquid flowing passages,
the two passages being divided by a heat exchanging partition plate
consisting of a plurality of synthetic resin plates which brings
both the fluids into indirect contact with each other, and both
walls of each air flowing passage are formed on an inverse U-shaped
member, corrugated side walls of the adjacent inverse U-shaped
members are bonded together by a rib portion provided protrusively
and coupled together at the side edges by a coupling panel, thus
forming the aforementioned liquid flowing passages.
As shown in FIG. 17, the heat exchanger described in the
aforementioned invention is suspended in several and so supported
in story inside of a packing material facing on an outer air inlet
port of the cooling tower, thus intending for prevention of a
whitish smoke or mist in wintertime.
In such prior art one, however, dust and microbe are capable of
sticking on a wall surface of the liquid flowing passage which is
narrowed and bent during a long period of service to thereby reduce
the liquid falling speed, thus a sectional area of the passage is
substantially narrowed, the liquid is hence prevented from falling
at a predetermined rate of flow, overflows on a feed side of the
heat exchangers, and thus not only the ambience is wet
unnecessarily, but also a loss may result on refrigerant.
In case the heat exchanger is suspended in several and so supported
in story inside of a packing material facing on an outer air inlet
port of the cooling tower (FIG. 17), whitish smoke or mist cannot
always be prevented due to an overflow phenomenon o the
aforementioned feed side, and further since the liquid flowing
passage is narrow, the air having come thereinto is hard to
extract, and thus is kept staying in the passage to hinder heat
exchange.
SUMMARY OF THE INVENTION
An object of the invention is to provide a heat exchanger unit
wherein if a loading is caused partly in a liquid flowing passage
at a main part for carrying out heat exchange of an indirect
contact type heat exchanger, a liquid feed/discharge rate can be
retained constant for the heat exchanger as a whole, thus no
influence will be exerted on a flow rate of the liquid flowing
passage, and the air having come thereinto can be extracted
smoothly, and also to provide the cooling tower using such heat
exchanger unit.
To attain the aforementioned object, a synthetic resin heat
exchanger unit for use on cooling tower of the particular invention
is a flat and thin hollow body, wherein the interior functions as a
liquid flowing passage, a cooling water feed part open externally
is formed on an upper portion of the hollow body, a discharge part
open eternally is also provided on a lower end of the liquid
flowing passage which is a lower edge of the hollow body, a major
breadth portion of the liquid flowing passage is intended for a
liquid falling speed reducing part, the liquid falling speed
reducing part has horizontally extending deflectors distributed
overall in story covering a plural stage, the deflectors are
dislocated every other to form a zigzag passage therebetween, the
liquid falling speed reducing part is disposed to abut on a
vertically extending overflowed-liquid escaping conduit through one
vertical sealing part at least, an upper end of the vertical
sealing part is shaped like a dam, the overflowed-liquid escaping
conduit and a reservoir portion on the uppermost stage in the
liquid falling speed reducing part communicate with each other
through the dam, an air vent crossing over the vertical sealing
part and opening into the overflowed-liquid escaping conduit is
formed at a bent position of the zigzag liquid falling speed
reducing part, a raise is formed as a spacer on outer surfaces of
both the wall plates.
Further, in a crossflow cooling tower incorporating therein an
indirect heat exchanger which comprises arraying adjacently a
plurality of synthetic resin heat exchanger units, a flat and thin
hollow body each, wherein the interior functions as a liquid
flowing passage, a cooling water feed part open externally is
formed on an upper portion of the hollow body, a discharge part
open externally is also provided on a lower end of the liquid
flowing passage which is a lower edge of the hollow body, a major
breadth portion of the liquid flowing passage is intended for a
liquid falling speed reducing part, the liquid falling speed
reducing part has horizontally extending deflectors distributed on
the overall hollow body in story covering a plural stage, a zigzag
passage is formed between the deflectors, using a raise formed on
both front and back of these heat exchanger units as a spacer,
forming a horizontal air flowing passage between the adjacent heat
exchanger units, said crossflow cooling tower being characterized
in that an air vent crossing over the vertical sealing part and
opening into the overflowed-liquid escaping conduit is formed at a
bent position of the zigzag liquid falling speed reducing part, an
upper edge of the hollow body is opened overall in breadth to
overhang both wall plates of the upper edge outwardly, a central
portion of the upper edge is formed into a U-shaped recession, the
cooling water feed part is formed on a bottom of the recession, and
when the heat exchanger units are arrayed adjacently in sequence
the cooling water feed parts come close each other to form a
temporary cooling water reservoir along an upper edge of the
indirect heat exchanger.
BRIEF DESCRIPTION OF THE DRAWINGS
A more complete appreciation of the invention and many of the
attendant advantages thereof will be readily obtained as the same
becomes better understood by reference to the following detailed
description when considered in connection with the accompanying
drawings, wherein:
FIG. 1 is a front view of a heat exchanger unit given in one
embodiment of the invention;
FIG. 2 is a side view showing the stage wherein the heat exchanger
units of FIG. 1 are arrayed in parallel;
FIG. 3 is a fragmentary front view showing a mode of another feed
part;
FIG. 4 is a plan view showing the state wherein the heat exchanger
units of FIG. 3 are arrayed in parallel;
FIG. 5 is a fragmentary front view representing another example of
a lower portion of the heat exchanger unit;
FIG. 6 is a schematic view of a crossflow cooling tower;
FIG. 7, FIG. 8 and FIG. 9 are sectional views taken on lines 7--7,
8--8, 9--9 of FIG. 1 respectively;
FIG. 10 is a fragmentary front view showing a shape of another
deflector of the heat exchanger unit;
FIG. 11 and FIG. 12 are schematic views showing an example of
another crossflow cooling tower each;
FIG. 13 is a schematic view representing another example of the
crossflow cooling tower according to the invention;
FIG. 14 is a general longitudinal sectional side view of another
embodiment of the invention;
FIG. 15 is a fragmentary schematic view of an example of the
cooling tower according to the invention;
FIG. 16 is a plan view of main part thereof; and
FIG. 17 and FIG. 18 are schematic views of a cooling tower in which
a prior art heat exchanger of this kind is incorporated.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENT
A typical example of the heat exchanger unit according to the
invention will then be described.
In FIG. 1, a reference numeral 10 denotes a heat exchanger unit,
the heat exchanger unit 10 comprises preferably a synthetic resin
flat hollow body obtained through vacuum molding or blow molding,
the interior functions as a liquid flowing passage, and while not
particularly limited, the synthetic resin may preferably be a cheap
and formable material such as polyvinyl chloride, polyethylene,
polypropylene or the like.
A cylindrical supplying port 11 which is a cooling water feed part
open externally is provided on an upper edge corner of the hollow
body 10, and also a discharge port 12 which is a cooling water
discharge part open externally is provided on the lower edge
corner. The supplying port 11 and the discharge port 12 are
positioned on the same side, or left side as illustrated, however,
the position is not necessarily so limited.
A peripheral sealing part 16 with a pair of wall plates 14, 15
deposited thereon is formed in the periphery of the hollow body 10
or the heat exchanger unit, and both the wall plates 14, 15 form
vertical sealing parts 19 deposited mutually along side edges 17,
18 of the heat exchanger unit 10 at positions in parallel with the
side edges 17, 18 and coming somewhat inward from both the side
edges 17, 18, and upper and lower ends of the left and right two
vertical sealing parts 19 do not reach upper and lower end edges
20, 21 of the heat exchanger unit 10, respectively.
Horizontally extending deflectors 22 with both the wall plates 14
and 15 deposited mutually therefor are distributed in story
covering a plural stage at central portions of the two vertical
sealing parts 19, these deflectors 22 are displaced every other, a
liquid falling speed reducing part 24 covering a major portion of
the breadth of the liquid flowing passage is formed between these
deflectors 22 as a zigzag passage 23, and both the wall plates 14,
15 in the liquid falling speed reducing part 24 function as a main
heat exchange surface of the heat exchanger unit 10.
A shape of the deflector 22 is not necessarily limited thereto, and
there may be a case where the liquid falling speed reducing part 24
is formed by distributing a multiplicity of horizontally-short and
discontinuous projections 22C and dislocating the projections 22C
vertically in order (FIG. 10).
On the other hand, narrow and vertical spaces between each vertical
sealing part 19 and the side edges 17, 18 function as an
overflowed-liquid escaping conduit 25, an upper end 26 of the
vertical sealing part 19 is shaped like a dam, an uppermost one 22a
of the deflectors 22 is formed to come somewhat lower than the
upper end 26, and the uppermost deflector 22a, the upper end edge
20 of the hollow body and both the wall plates 14, 15 form a liquid
reservoir 40. The liquid reservoir 40 and the overflowed-liquid
escaping conduit 25 communicate with each other through the dam
26.
Barring the liquid reservoir 40, the liquid falling speed reducing
part 24 is divided into two sequences of liquid flowing passages
23a, 23b, as illustrated, by a vertical and discontinuous partition
sealing portion 50 at the central portion. However, liquid flowing
passages in four sequences or more may be formed, as desired, by
increasing the number of sealing portions 50.
An air vent 60 crossing over the vertical sealing part 19 and
opening into the overflowed-liquid escaping conduit 25 is formed at
a position of each bent passage 24a of the zigzag liquid falling
speed reducing part 24, namely an upper corner of each bent passage
24a, and a raise 70 is formed on outer surfaces of both the wall
plates 14, 15 as a spacer.
Further, both walls of the zigzag passage 23 between
vertically-adjacent and horizontally-extending reflectors 22 in the
synthetic resin heat exchanger unit 10 for use on cooling tower are
corrugated with parallel ridges 80 inclined gradually at 45 degrees
or so toward the downstream side formed on almost overall surfaces
of both the walls.
The overflowed-liquid escaping conduit 25 may be provided on one
side edge 17 or 18 only, and, as shown in FIGS. 3 and 4, the upper
end edge 20 of the hollow body 10 is opened in full width and both
wall plates 14, 15 are overhung externally at an even height with
the raise 70, a U-shaped recession 20a is formed at central portion
of the upper end edge 20, a supplying port 11a is formed on a
bottom of the recession 20a, the upper end edges 20 of the heat
exchanger units 10 adjacent at the time of assembly come in contact
close with each other on the outer peripheral surfaces, and the
longitudinally-extending liquid reservoir 20b may be formed of the
group of recessions 20a. Further, the lower end edge 21 of the
hollow body may be opened in full width, thereby substituting for
the discharge port 12 in function.
Then, a sectional area of the overflowed-liquid escaping conduit
may not necessarily be uniform in size but large on an upper
portion of the heat exchanger and small on a lower portion.
A function of the heat exchanger unit 10 constructed as above will
be described along with a function of a crossflow cooling tower A
of the associated invention.
First, a plurality of heat exchanger units 10 are disposed in
parallel by means of a case or other proper support frame (not
indicated), and a narrow horizontal air flowing passage 33 is
formed between the adjacent heat exchanger units 10 with the raise
70 as a spacer, thereby assembling an indirect contact type heat
exchanger B of desired dimensions (FIG. 2).
The heat exchanger B thus assembled is arrayed inside of a packing
material C of the crossflow cooling tower A as shown in FIG. 6. In
this case, a feed pipe E for feeding a cooling water to an upper
water tank D on the top of packing material C branches halfway, and
a branched pipe F is provided with a valve G and intended for a
supplying header to the group of heat exchanger units 10.
A blower of the cooling tower A is then driven to rotate, the
cooling water or a circulating refrigerant warmed up (30 to
70.degree. C.) by a load K such as air conditioner, refrigerator or
the like is fed to a position of the liquid falling speed reducing
part 24 from the feed part of each heat exchanger unit through the
supplying header F, then the cooling water flows successively in
the zigzag passage 23 formed between the deflectors 22 and comes in
contact with the wall plates 14, 15 as stirred for the time longer
by far than it merely flows vertically, each air flowing passage 33
is thus subjected to a heat exchange with the air flowing
horizontally therethrough, and the cooling water itself has the
heat removed by the air and so cooled down.
Both walls of the zigzag passage 23 between the deflectors 22 are
corrugated with the parallel ridges 80 inclined gradually up to 45
degrees or so toward the downstream side formed almost on overall
surfaces of both sides, therefore the cooling water circulating in
the zigzag passage 23 is guided upward to rise somewhat whenever it
gets over the ridges 80, comes up full to the upstream portion or
wets at least an inside wall surface of the horizontal part as high
as its upper portion, reaches the bent position 24a and then keeps
contact with almost overall surfaces of both the wall plates for a
long time.
During operation of the cooling tower, the air remaining in the
liquid falling speed reducing part 24 is pushed to an upper corner
of the bent passage of the liquid falling speed reducing part 24
according to a move of the cooling water rising somewhat upward by
the ridges 80, and is to stay at the portion, however, it flows
into the overflowed-liquid escaping conduit 25 through the air vent
60, climbs in the overflowed-liquid escaping conduit 25, and is
discharged externally from the supplying port 11.
Then, in case the group of heat exchanger units 10 are placed one
upon another in story and so disposed inside of the packing
material C, the air having come in contact direct with the cooling
water on the packing material C to cool it down and also risen in
temperature itself to a high absolute temperature flows all into
all the air flowing passages 33 of the heat exchanger unit 10.
On the other hand, the cooling water falling zigzag in the liquid
falling speed reducing part 24 of the upper heat exchanger unit 10
flows successively into the liquid falling speed reducing part 24
of the lower heat exchanger unit 10 from the supplying port 11, the
flowing cooling water is indirectly cooled by the air passing
through the air flowing passage 33, and the air having thus risen
itself in temperature is exhausted outside the cooling tower
without a whitish smoke or mist from an exhaust port (FIG. 6).
If supply of the cooling water causes a pulsation, supply increases
momentarily, or a microbe comes to stick in the liquid falling
speed reducing part 24, a sectional area of the liquid falling
speed reducing part 24 is narrowed to invite a deterioration of the
rate of flow, a level of the liquid reservoir rises to be higher
than the dam 26, the cooling water falls partly through the
overflowed-liquid escaping conduit 25, and does not come out of the
supplying port 11 of the heat exchanger unit 10.
Then, during operation of the cooling tower A, the supplying port
11 of each heat exchanger unit 10 is left open to the air, and the
cooling water flows down naturally as zigzagging in the liquid
falling speed reducing part 24. Simultaneously with shutdown of the
cooling tower, it is subjected to the atmospheric pressure and
discharged externally from the discharge port.
Further, the upper end edge 20 of the hollow body 10 is opened in
full width and both the wall plates 14, 15 of the upper end edge 20
are overhung outwardly at the even height with the raise 70, the
central portion of the upper end edge is formed into the U-shaped
recession 20a, the supplying port 11a is formed at a bottom portion
of the recession 20a, and in case the recessions 20a of the heat
exchanger units 10 abutting each other at the time of assembly come
in contact close with each other on an outer peripheral surface of
the upper end edge 20, thus forming the longitudinally-extending
cooling water reservoir 20b (FIG. 3), the plurality of heat
exchanger units 10 are disposed adjacently in parallel, and thus an
upper end edge of the heat exchanger B is intended for the cooling
water reservoir 20b, the supplying header F is piped horizontally
in the reservoir 20b, the cooling water is fed to the reservoir 20b
from the supplying header F and is allowed to flow into each heat
exchanger unit 10 from the externally-opened supplying port 11a
provided on the bottom portion of the recession 20a of each heat
exchanger unit 10 which constitutes the reservoir 20b (FIG. 4).
As described, a cooling water is fed to each heat exchanger unit
10, air is flowed horizontally to the air flowing passage 33
between the heat exchanger units 10, and the air and the cooling
water are thus subjected to an indirect contact heat exchange.
Then, for using the heat exchanger unit 10 as an enclosed one, a
discharging head (not indicated) similar to the supplying header F
is connected to the discharge ports 12, however, it goes without
saying that the cooling water flowing internally and water applied
on the outer surface of each heat exchanger unit 10 will be kept
from mixing with each other during use.
Further, the heat exchanger unit 10 with the discharge port 12
formed by opening the lower end edge 21 of the hollow body in full
width is disposed on the top of packing material C, and is intended
for distributing the cooling water uniformly to the top of packing
material C to prevention of whitish smoke or mist (FIG. 5, FIG.
10).
There may be a case where a three-way valve is used as the valve G,
thereby adjusting the ratio of a rate of flow of the cooling water
to be fed to the packing material to a rate of flow of the cooling
water to be fed to the indirect contact type heat exchanger B
correspondingly to a cooling temperature. That is, where the
cooling temperature is rather high as in wintertime, a rate of flow
of the cooling water to be fed to the packing material is
minimized, but the cooling temperature is low as in summertime, a
rate of flow of the cooling water to be fed to the packing material
is increased, thus operating the three-way valve accordingly.
Despite the above-described embodiment, the crossflow cooling tower
of the associated invention will remain same even from disposing
the aforementioned indirect contact type heat exchanger B on a
lower side of the upper water tank D in parallel with the packing
material C, and in this case, a branched pipe and a valve are not
required, and a piping structure may be simplified accordingly. The
above description for function refers to the case where the season
is winter or the air temperature is low, therefore when the air
temperature is high like summertime, the valve G of the supplying
header is closed, and thus supply of the cooling water to the heat
exchanger unit 10 is stopped.
FIG. 11 and FIG. 12 represent another example of the cooling tower
according to the invention, each.
In FIG. 11, first indirect contact type heat exchangers B.sub.1 are
disposed in parallel inside a wet heat exchanger or the packing
material C disposed on a lower side of the upper water tank D of
the cooling tower A, further a second indirect contact type heat
exchanger B.sub.2 is disposed in story between the wet heat
exchanger C and the upper water tank D, which comes in a value
adding heights of the first indirect contact type heat exchangers
B.sub.1, and a feed part of the first and second indirect contact
type heat exchangers B.sub.1, B.sub.2 opens opposite to shrinkler
holes D.sub.1. Function and effect of the example are same as those
of the aforementioned invention, a dry air high in temperature and
low in relative humidity is easy to obtain.
In FIG. 11, the first indirect contact type heat exchangers B.sub.1
are disposed outside or inside of the wet heat exchanger or packing
material C disposed on a lower side of the upper water tank D of
the cooling tower A, the second indirect contact type heat
exchanger B.sub.2 is disposed in story between the wet heat
exchanger C and the upper water tank C, a height of the first
indirect contact type heat exchanger B.sub.1 comes in a value
adding heights of the wet heat exchanger C and the second indirect
contact type heat exchanger B.sub.2, a nose of a distributing pipe
H extending from the upper water tank D is opened to a feed part of
the inside indirect contact type heat exchanger B.sub.1, while a
feed part of the outside indirect contact type heat exchanger
B.sub.1 is opened opposite to the shrinkler holes D.sub.1 on a
bottom of the upper water tank D. Function and effect of the
example are same as those of the aforementioned invention, and thus
the example is suitable for obtaining a dry air high in temperature
and low in relative humidity from raising temperature of the air
once and then feeding it to the wet heat exchanger and the dry heat
exchanger. Then, in the crossflow cooling tower of the invention,
it is not particularly required to provide an upper water tank, and
a cooling water can be fed smoothly to each liquid flowing passage
in a plurality of heat exchanger units constituting the
aforementioned heat exchangers from a temporary reservoir formed on
an upper end edge of the heat exchangers without increasing the
number of parts therefor, and further heat exchanger units for the
heat exchanger can easily be replaced.
Next, a further example of the crossflow cooling tower according to
the invention will be described with reference to FIG. 13.
In the drawing, a reference numeral 110 denotes a cooling tower
shell, a lower water tank 111 is provided on its lower portion, the
packing material C with a multiplicity of tongued-and-grooved
plates raised thereon is provided on a lower stage within the
cooling tower shell 110, a first sprinkler 113 capable of feeding a
cooling water to the packing material C is provided right thereon,
which has a multiplicity of fine holes perforated in a baseplate of
a shallow water tank as illustrated, however, it is not
particularly limited to such type. An air intake grille 116 is
provided on the cooling tower shell 110 corresponding to one end
surface of the packing material C, and in this mode of operation, a
portion of the packing material C functions as one kind of direct
contact type counterflow or crossflow heat exchanger.
In the invention the indirect contact type heat exchanger B is
provided particularly on an upper portion of the first sprinkler
113, and a plane area per single capacity is almost same as that of
the packing material C. The heat exchanger B is same as that of
working in the aforementioned mode of operation.
Such heat exchangers B are disposed in parallel with a common
supply side header 132 at predetermined intervals, and discharge
ports of the heat exchangers are opened onto the first sprinkler
113.
A second air intake grille 131 is opened on a side wall of the
shell 110 with the heat exchangers B positioned thereon, an air
current control plate 135 reciprocating between a duct 134 through
which the packing material C and an exhaust port 133 communicate
with each other and an air passage outlet of the heat exchanger B
is provided inside of the heat exchanger B with its lower end
supported on a frame in the cooling tower, which can be fixed at an
arbitrary angle from vertical position to horizontal position.
A second sprinkler 136 is provided further over the heat exchanger
B, which may be such one as is similar to the first sprinkler 113
in structure.
A supply pipe for supplying a cooling water ranging to the load
such as air conditioner, refrigerator and the like is forked
through a transfer valve 138, one branched pipe 139 is connected to
each heat exchanger unit of the heat exchanger B by way of the
supply side header 132, and another branched pipe (second supply
pipe) 140 is connected to the second sprinkler 136.
In the mode of operation constructed as above, the transfer valve
138 is changed to a side of the one branched pipe 139 so as to
allow the cooling water to flow when the air temperature is low,
the air current control plate 135 is positioned on a chain line so
indicated in FIG. 13 or around with the angle of inclination
determined according to the then air temperature and load, and from
operating the circuit of the cooling tower, the cooling water
passes through each bent liquid flowing passage of the heat
exchanger B by way of the supply side header 132, and flows into
the first sprinkler 113, and is applied to the lower packing
material C, flows into the lower water tank 111, and then returns
to the load to recirculation thereafter.
On the other hand, the air comes in through the air intake grilles
116, 131, the cooling water comes in contact direct with the air
coming in through the air intake grille 116 at the packing material
C, evaporates partly, then the cooling water is cooled on a latent
heat of the vaporization, exchanges heat therewith, and the air
having risen in temperature climbs from the duct 134.
On the other hand, the air having come in through the second air
intake grille 131 passes through the air flowing passage 133 of the
heat exchanger B and is subjected to an indirect contact heat
exchange with the internal cooling water through the wall plates
14, 15 of each heat exchanger unit, the heated air flows into the
duct 134 by way of the air current control plate 135 and is mixed
with the wet air in the duct 134, thus decreases relative humidity,
raises temperature and is then exhausted from the exhaust port 133.
Accordingly, even if cooled down on the air, it is hard to get a
whitish smoke or mist.
Next, if the transfer valve 138 is changed to a side of the other
branched pipe 140 to operation when the air temperature is high,
the cooling water is first fed to the second sprinkler 136, thus
sprinkled to an outside of each heat exchanger unit 10 of the heat
exchanger B, i.e. to a side of the air flowing passage, wets an
outer surface of each heat exchanger unit 10 and flows down into
the first sprinkler 113 once, and is then sprinkled over the
packing material C as in the case of wintertime and then passes
through the load K from the lower water tank 111 to
recirculation.
Accordingly, in a portion of the heat exchanger B, the air from the
upper air intake port 131 and the cooling water come in contact
directly with each other, and thus the cooling water evaporates
partly and is cooled down on its latent heat, a cooling effect at
the portion of the heat exchanger B may compensate it thoroughly
for increase of the load.
FIG. 14 is a diagram showing a case where a typical one in the
above described modes of the invention is applied to a closed type
cooling tower. In the embodiment as in FIG. 4, since an expansion
tank (a reservoir) required for the closed type cooling tower is
placed in a casing, the entire system can be simple. In the
drawing, like reference characters represent like parts, and hence
a further description will be omitted thereof here.
The cooling water storage tank 111 is provided on a lower side of
the heat exchanger B, and a capacity of the cooling water storage
tank 111 is larger than the capacity of the liquid flowing passage
in each heat exchanger unit of the heat exchanger, or preferably
1.5 to 2 times as large as that, and the discharge port of each
heat exchanger unit is opened to an upper opening 111a of the
cooling water storage tank 111. The discharge port may be coupled
to the opening 111a through the common discharge side header. In
this case the opening 111a is exposed to the air, thus forming an
air passage.
The cooling water storage tank 111 is provided within the shell 110
of the cooling tower A, a cooling water pipe 227 is connected to
the load K from a lower portion of the cooling water storage tank
111 through a valve 228 and a pump 229, and is further connected to
a header 223 through a valve 231, thus forming a circuit for the
cooling water system.
An air intake port 232 is formed on a portion of the shell 110
where the heat exchanger B is provided, a vertical air adit 233 is
formed in the shell 110 on a counter side, a drop water tank 234 is
provided on a lower end of the air adit 233, and an exhaust port
235 is provided on an upper end of the air adit 233.
A sprinkler 236 is provided on the heat exchanger B, water
sprinkled thereby is collected into the drop water tank 234 through
an inclined plate 237 provided between the heat exchanger B and the
cooling water storage tank 111, which is connected to the sprinkler
236 through a pipe 238, a valve 239 and a ram 240, thereby
configuring a sprinkling system circuit.
It is then preferable that an automatic water supply system 241
having a valve operated according a water level be provided on the
cooling water storage tank 111.
In such mode of operation, when the system is operated, water in
the cooling water storage tank 111 flows into the common header 223
by way of the load K, the cooling water comes into the cooling
water passage in each heat exchanger unit of the heat exchanger B
through a pipe 225, and while flowing in each bent passage, it is
subjected to heat exchange with the air and the sprinkled water
through both the wall plates 14, 15, and is then returned to the
cooling water storage tank 111 from a discharge port 222 to
circulation.
In the invention constructed as described above to function, each
heat exchanger unit is air communicating type, and the lower
discharge port is connected to the common lower cooling water
storage tank, therefore when operation of the cooling tower is
stopped, the cooling water in all the heat exchanger units is
replaced by the air to flow into the lower storage tank, and hence
the cooling water is not capable of freezing within the heat
exchanger units. Then, in the unlikely event that a quantity of the
cooling water fluctuates, only a quantity of the air brought into
the heat exchanger units may fluctuate accordingly, and thus the
cooling water passage in the heat exchanger units will never be
negative in pressure or collapsed by the atmospheric pressure.
Accordingly, such metal as is thin and small in mechanical strength
may be employed for the metallic heat exchanger unit, which is
serviceable for light-weight construction to realize.
FIG. 15 and FIG. 16 represent one embodiment of a crossflow cooling
tower using a heat exchanger with a multiplicity of heat exchanger
units shown in FIGS. 3, 4, 5 and 10 disposed in parallel
therefor.
In FIG. 15, a reference character A represents a crossflow cooling
tower provided with a whitish smoke preventive function, wherein
synthetic resin made indirect contact type or dry heat exchanger B
is arrayed in story over a plurality of packing materials or wet
heat exchangers C, a blower 313 is provided on an exhaust port 312
for exhausting a mixture of the wet air having passed the wet heat
exchanger C and the dry air having passed the dry heat exchanger B,
which is characterized in that an air intake port 316 facing on an
air blow-off port 315 of an air passage 314 of the dry heat
exchanger B is provided, a plurality of dry/wet air mixing
cylinders 300 are disposed at regular intervals and so overhung
horizontally under the exhaust port 312, an air intake height of
the cylinder 300 corresponds to a full height of the air blow-off
port 315, a nose portion of each cylinder 300 is closed 317, an air
discharge port 318 is opened on a peripheral surface of the
cylinder 300 ranging from a side of the air blow-off port 315 to a
nose side, the cylinder 300 functions as an air release guide
chamber 319 internally.
The air discharge port 318 for the cylinder 300 is perforated in an
upper wall of the cylinder 300.
There may be a case where the air discharge port 318 for the
cylinder 300 is perforated in opposite side walls of the cylinder
300.
Further, there may be a case where a wet air intake port 321 opened
into the cylinder 300 is perforated in a bottom portion 320 of the
cylinder 300 near to the closed end portion 317.
The upper wall of the cylinder 300 in which the air discharge port
318 for the cylinder 300 is perforated is inclined downward from an
upper end of the air blow-off port 315 downwardly of the blower 313
so as to keep away from blades of the blower 313, the bottom
portion 320 of the cylinder 300 is inclined upward, counter to the
upper wall, from a lower end of the air blow-off port 315
downwardly of the blower 313, thus functioning as a drop receiving
part, which is desirable for suction of the dry air and recovery of
the drop.
The cylinder 300 is made generally of synthetic resin.
A function of the aforementioned construction according to the
particular invention will be described next.
A cooling water fed from refrigerator or the like is sprinkled to
fall from upper portion of the synthetic resin made dry heat
exchanger, and while falling the cooling water is subjected to an
indirect contact heat exchange with the air taken externally into
an air passage of the dry heat exchanger and thus cooled down, then
it is sprinkled over the wet heat exchanger arrayed in story under
the dry heat exchanger, and while falling on the surface of the wet
heat exchanger it comes in contact direct with the air, and the
cooling water is cooled down to a predetermined temperature on an
action of latent heat, collected in a lower water tank of the
crossflow cooling tower, circulated to use on the load such as
refrigerator or the like, and after temperature rise again, it is
refed to the dry heat exchanger.
Meanwhile, the wet air with the absolute humidity raised by heat
exchange in the wet heat exchanger passes through the wet heat
exchanger on a suction of the blower provided on the exhaust port
and then climbs toward the exhaust port.
Then, the dry air with the absolute humidity unchanged by heat
exchange in the dry heat exchanger is also subjected to a suction
of the blower, and most of the dry air flows into the release guide
chamber from the air blow-off port of the air-passage of the dry
heat exchanger by way of the air intake port of each cylinder, and
some quantity of the dry air is discharged between adjacent
cylinders.
Next, the dry air thus dispersed and distributed in the dry air
release guide chamber is released toward the exhaust port from the
discharge port of each cylinder as keeping the state of almost
laminar flow, sucked in the exhaust port uniformly together with
the aforementioned some quantity of dry air, and the wet air stream
climbs through a vertical passage formed between the adjacent
cylinders. The climbing wet air flows along a peripheral surface of
the cylinder and is sucked to climb toward the exhaust port as
almost laminar flow along with a flow of the dry air released from
the air blow-off port. That is, both flows will not be turbulent
but arrive at the blower as keeping laminar flows parallel with
each other, flows of the dry air and the wet air distributed fine
mutually by rotating blades of the blower of small power are
agitated and exhausted without mist as a mixture with the absolute
humidity adjusted. In other words, the air is exhausted outside the
cooling tower without generating whitish smoke.
Where the air discharge port of the cylinder is perforated in an
upper wall of the cylinder, a flow of the dry air will never be
turbulent and sucked toward the exhaust port.
Where the air discharge port of the cylinder is perforated in
opposite side walls of the cylinder, the dry air coming out of the
air discharge port is mixed somewhat with the wet air to a cross
flow, climbs then along a peripheral surface of the cylinder and is
sucked toward the exhaust port.
Further, where the wet air intake port opened into the cylinder
near to the closed end portion is perforated in a bottom portion of
the cylinder, a part of the wet air is dried in the release guide
chamber, the mixture is then released toward the exhaust port and
sucked as a laminar flow.
Obviously, numerous modifications and variations of the present
invention are possible in light of the above teachings. It is
therefore to be understood that within the scope of the appended
claims, the invention may be practiced otherwise than as
specifically described herein.
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